The present invention relates to computer keyboards. More particularly, the present invention relates to a remote, wireless, programmable keyboard input system for computers in which a plurality of remote transmitters can simultaneously transmit I D Codes to a single receiver. The remote transmitters send fixed radio frequency (xe2x80x9cRFxe2x80x9d) or infrared (xe2x80x9cIRxe2x80x9d) wave I D Codes to the receiver. The receiver is connected to the keyboard port of a computer""s central processing unit. The computer""s standard keyboard connects to the receiver and remains fully functional. The receiver has the capacity to recognize the ID-Code transmitted by a particular button on a transmitter and to associate that code with a particular scancode sent by a key of a standard keyboard. The invention permits customization of the receiver and the associated scancodes held in its memory through a programming sequence that involves the receiver, the transmitter and the computer""s standard keyboard.
Definition of terms used in this Patent Application:
1. xe2x80x9cButtonxe2x80x9d
The user activated controls on the transmitter. In the preferred embodiment these are membrane switches, but could be any type of switches or sensors that send a closed/open signal to the transmitter""s circuitry.
2. xe2x80x9cID-Codexe2x80x9d
An identification code that is sent by the transmitter when one of its Buttons is pressed. The ID-Code includes a transmitter number and a button number. The ID-Code for each Transmitter and each Button is assigned at the time of manufacture. The ID-Code is sent by means of emitting a modulated packet of radio frequency wave pulses or infrared light pulses.
3. xe2x80x9cKeyxe2x80x9d
The keys on a standard keyboard.
4. xe2x80x9cKeyboard portxe2x80x9d
The hardware interface socket on the computer""s central processing unit (CPU) where the standard keyboard is connected. On a laptop computer it is the socket where an external standard keyboard is connected.
5. xe2x80x9cModified Scancodexe2x80x9d
The scancode sequence that results when one or more modifier keys are held down while pressing another key.
6. xe2x80x9cModifier Keyxe2x80x9d
A key on the standard keyboard that, when held down while pressing one of the other keys, modifies the meaning of the other key. Examples of modifier keys are: xe2x80x9cShiftxe2x80x9d, xe2x80x9cControlxe2x80x9d, xe2x80x9cCommandxe2x80x9d, xe2x80x9cAltxe2x80x9d, and xe2x80x9cOptionxe2x80x9d.
7. xe2x80x9cReceiverxe2x80x9d
The hardware device, connected between the standard keyboard and the keyboard port, that recognizes and accepts ID-Codes from transmitters with which it has previously been trained to recognize, associates each ID-Code with the scancode, or modified scancode, learned in the training sequence and held in its memory, and sends that scancode on to the CPU, the same as if it were coming from the standard keyboard.
8. xe2x80x9cScancodexe2x80x9d
A binary code that identifies a key that has been pressed or released on a standard keyboard. This code is sent by the standard keyboard to the keyboard port. In the programming method, the receiver monitors and learns these scancodes and holds them in its memory.
9. xe2x80x9cStandard keyboard xe2x80x9d
The original, normal, xe2x80x9ctypewriterxe2x80x9d style keyboard that is generally included with a desktop personal computer. Note: For a portable, laptop computer, an externally connected standard keyboard must be attached to the receiver for the programaing method described herein to function as designed.
10. xe2x80x9cTransmitterxe2x80x9d
The hand held remote device that sends fixed radio frequency ID-Codes. Several transmitters may send their ID-Codes to a single receiver that has been defined to recognize these ID-Codes. The same transmitter""s ID-Codes can also be recognized by more than one receiver.
Manipulation and entry of keyboard input into a computer""s central processing unit is often accomplished through the use of a standard keyboard. A standard keyboard sends scancodes which are represented by electrical signals to the central processing unit. Standard keyboards are typically connected to the keyboard of the central processing unit by a connector wire. Each central processing unit is typically connected to only one standard keyboard and, therefore, only receives keyboard input from this single source.
Most standard keyboards also limit transmission to a single alpha-numeric character at a time. If the user wishes to transmit multiple characters or instructions with a single keystroke, xe2x80x9cmacroxe2x80x9d commands must be created within the specific individual software program being used, the standard keyboard is us ed merely to access the macro. Advances in keyboard technology have also produced keyboards that can be programmed to transmit macros.
The traditional configuration is cumbersome and limiting inasmuch as a single user must remain stationary in relationship to a computer to input keystrokes. As advances in technology have occurred, the need for remote keyboard input systems has become evident.
Attempts to overcome some of the shortcomings of standard computer input systems have been made. The advancements have generally focused on specific needs or functions. For example, U.S. Pat. No. 4,775,928 to Kendall, et al., teaches a hand-held wireless computer controller system. The device is a battery powered control station that transmits alpha-numeric characters and control functions to a receiver interfaced with a host computer via an RS 232 serial link. The receiver echoes back the transmitted information to the control station where it is visualized on a display. While providing advancements in remote transmission of data to a central processing unit, there are several shortcomings to this patent. A first shortcoming of this device is that it permits only a single control station to interface with a central processing unit. The patent does not teach or discuss the possibility of several remote stations accessing a central processing unit simultaneously. It follows that the patent offers no teaching of the ability to record the chronology of responses received from multiple transmitting stations. A second shortcoming of this device is that it enters the computer through an RS 232 port, not the CPU""s keyboard port; it is therefore limited to use by special software written to look for these alpha-numeric characters and control functions at this RS 232 port. It cannot interface with off-the-shelf software that looks for scancode input at the keyboard port. Yet another shortcoming of this art is that the keystrokes are predefined. The patent does not teach ability to the program individual keys for the transmission of input specific to a software application.
Further improvements in wireless remote transmission systems are seen in U.S. Pat. Nos. 5,093,786 (RE 35,449) and 5,379,213 to Derks. U.S. Pat. No. 5,093,786 (RE 35,449) discloses a wireless transceiving device in which a plurality of remote response units interface with a central control unit for transmission of input, such as answers to questions posed, from the remote response units to the control unit. The central control unit checks for a valid response and, once a valid response is received, places the remote response unit in an xe2x80x9coffxe2x80x9d position. While this patent offers advances to the art of wireless remote transmission of input, namely increased transmission speed and multiple remote user capabilities, it is not without shortcomings. First, the patent does not teach the possibility of programmable keypads. Second, input received by the control unit is not captured chronologically, only valid responses are acknowledged, the order in which they are received is not relevant. A third shortcoming of the device is that the system is software controlled, making installation unduly burdensome and requiring use of valuable memory. Again, the controller enters through an RS 232 serial port rather than the standard keyboard port of the CPU. It cannot be used with off-the-shelf software.
U.S. Pat. No. 5,379,213, also to Derks, teaches a testing system and method in which multiple test takers equipped with remote response units can be simultaneously tested. This patent relies upon the same basic technology as the other cited Derks patent. Test takers respond to written questions by activating a keystroke. The central processing unit receives and stores the response which is then evaluated. Like the prior cited Derk""s patents, this art offers advances in the transmission of input from multiple remote units, but it also suffers from the same shortcomings as the other Derk""s patent, namely: it does not provide for programmable keystrokes, it does not permit the chronological sequences of responses from various user, and it is internal software dependent.
Other examples of wireless data transmission systems are seen in U.S. Pat. No. 5,515,051 to Tanaka et al., and U.S. Pat. No. 4,654,818 to Wettenauer.
As a result, there is need for an input transmission system for computers which permits multiple remote unit users to simultaneously transmit input signals to a receiving unit. The system should further provide for the sequential recognition of each signal transmitted by the remote units. The system should further permit the programming to associate particular buttons on particular transmitters with any required standard keyboard key or modified key. The system should not be dependent upon internal software and should be capable of interacting with any software that uses standard keyboard scancode input and should be easy to install and use.
It is therefore an object of the present invention to provide a wireless remote standard keyboard input system for computers which enables multiple remote unit input to occur simultaneously, wherein each input signal is received in the order in which it is sent, associated with a related scancode, and entered into the computer""s CPU keyboard port in the same chronological sequence.
It is another object of the present invention to provide such a system which operates using either radio frequency wave or infrared wave technology.
It is a further object of the present invention to provide such a system in which the receiver may be programmed to associate transmitted ID-Codes from a particular transmitter button to specific scancodes representing specific keys or modified keys from the standard keyboard.
It is yet a further object of the present invention to provide such a system in which the receiving unit can be plugged into the keyboard port of the CPU without disabling the standard keyboard of the computer.
The objects of the invention are provided in a wireless, remote programmable keyboard input system for computers and method for programming same. According to the invention, a single receiving unit capable of receiving ID-Code transmissions from multiple remote transmitters is plugged into the keyboard port of a central processing unit. The receiver is adapted to permit the computer""s standard keyboard to be plugged into it and continue to operate normally through it. The receiver accepts ID-Codes transmitted by the remote transmitters, identifies the button and the transmitter from which the ID-Code has been received, and associates this ID-Code with a related scancode and transfers this scancode to the central processing unit. If the associated scancode is for a modified key, the scancode for the modifier key(s) is (are) sent before the scancode for the modified key.
In this embodiment, the remote transmitters are battery powered, hand held devices, having a face containing multiple buttons. Each button transmits a unique ID-Code to the receiver. The receiver associates the ID-Code with a single scancode or a modified scancode from the standard keyboard. However, an alternate embodiment envisions the receiver having the capability to associate this ID-Code with multiple scancodes from a series of keys or modified keys, via a xe2x80x9cmacroxe2x80x9d command, as defined in the programmable aspect of the invention.
Programming occurs in the receiver in a three step process: (1) the programming sequence is initiated by activating a switch located on the receiver, (2) the transmitter button to be defined is then depressed, and (3) the corresponding key or modified key on the standard keyboard is depressed. After completion of the programming phase, pressing that button on that remote transmitter transmits a fixed xe2x80x9cRFxe2x80x9d or xe2x80x9cIRxe2x80x9d ID-Code, it is recognized by the receiver as corresponding to the previously selected standard keyboard scancode or modified scancode. In an alternate embodiment, multiple standard keyboard scancodes may be triggered in the receiver through a single remote transmitter button by creation ofxe2x80x9cmacroxe2x80x9d commands in the Device""s receiver.